Mobile speaker unit



FIG. 1 is a front isometric view of a mobile device unit, embodying mynew design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a rear elevation view thereof; and,

FIG. 6 is a top plan view thereof.

CLAIM The ornamental design for a mobile speaker unit, substantially as shown. 